Integrating Green Infrastructure into Regional Planning

2010 APA Conference

New Orleans, LAApril 12, 2010

Speakers

• State of the Practice & Green Infrastructure Concepts• Don Kostelec, AICP; • Transpo Group, Asheville, NC

• Linking Lands & Communities in the Land-of-Sky Region• Linda Giltz, AICP; • Land-of-Sky Regional Council, Asheville

• Jacksonville Collector and Green Streets Plan• Don Kostelec substituting for Chris Lukasina

Objectives

• Appreciate how a regional GI network/plan can be used and integrated with other regional and local plans and practices.

• Know state-of-the-practice techniques • Understand the value in assessing and identifying green

infrastructure at a regional, landscape scale.• Gain insight on what to consider if you want to

undertake similar projects.

Being Green is Contextual• Not all things are as they

appear• Some bad may come as a

result of a lot of good• Elected officials don’t like

these types of tradeoffs & uncertainties

• Planners need to understand the good/bad and the tradeoffs to be effective

Defining Green Infrastructure - Natural Environment

• Green Infrastructure is a region’s Natural Life Support System – an interconnected network of land and water that contributes to the health, economic well being & quality of life for communities & people.

Defining Green Infrastructure - Natural Environment

• A GI Network may include:• Natural areas• Public and private conservation

lands• Farmlands and lands managed for

forestry• Outdoor recreation areas and trails• Cultural resources and sites

• GI networks exist at various scales (parcel, community, regional)

Defining Green Infrastructure - Built Environment

• Green infrastructure is a way for municipalities, developers, engineers and planner to provide for urban infrastructure that supports and improves the region’s natural resources, including:• Land, Water, Forests,

Air, Etc.

Defining Green Infrastructure - Built Environment

• A GI Network may include:• Reduced impervious structures• Stream buffer requirements• Stormwater management practices that treat

water at its source• Street design that promotes efficient

transportation (e.g. connectivity policies)• Provides for safe travel by pedestrians,

bicyclists and transit users.

• Again, GI networks exist at various scales (parcel, community, regional)

Green Infrastructure Policies

• There is a direct correlation between land use patterns, the way a site is developed and environmental degradation. Well-planned growth using good site design and development practices can restore and prevent environmental degradation and enhance community character.

RI Department of Environmental Management

Characteristics of Policy/Regulations

• Regulations are often developed with no research base.• Regulations are often developed as an emotional response to

some phenomena.• Regulations are often imposed by layers of cumbersome

structure.• Regulations have many benefits including protecting the

health, safety and general welfare of the public.

• Regulations serve as a “bar” or standard for the regulator.

• Regulations often impose maximums.• Regulations often impose minimums (e.g. EPA,

federal).• Regulations that are vague sometimes allow

environmental initiatives

Characteristics of Policy/Regulations

Impervious Surfaces

Impervious Surfaces

Typical Language in an Ordinance

•“All built-upon areas shall be designed and located to minimize stormwater runoff impacts to the receiving waters and minimize concentrated stormwater flow.”

• Ideal?

• Too vague?

• Too restrictive?

• Don’t know?

Impacts of Stormwater• Urban stormwater

contributes to:• 13% of impaired rivers and

streams;• 21% of impaired lakes;• 46% of impaired estuaries;• 55% of impaired ocean

shorelines

Stormwater BMP Maintenance & Inspection

Impacts of Stormwater

• Addressed through:• Controlling stormwater

runoff• Low impact

development techniques

• Green architectural techniques

• Green parking lots

Low Impact Development

Conventional Development

• Minimize Land Clearing • Removal of most or all native vegetation

• Amended soils • Compacted soils

• Minimize use of impervious surfaces • Excessive use of impervious surfaces

• Provide for infiltration • Costly infrastructure

• Fit development to the natural hydrology

• Severely altered hyrdrology

Street Connectivity as a Green Infrastructure practice

• Cities are looking at a host of transportation, land use, energy, environmental and sustainability policy issues and considering new measurement techniques:• Complete Streets Policy• Concurrency Program

Refinements• VMT and GHG per Capita

Reduction

Background Policy Issues

• Multi-Modal Level-of-Service (LOS)

• Street Connectivity Policies Connectivity between new/existing

developed lands Non-motorized public accessways

and limiting cul-de-sacs Grid-based standards for streets

(500 feet ) and Non-motorized (330 feet) – emphasis on smaller block lengths

Developing connectivity metrics

Systems Connectivity is ImportantMeasuring and quantifying system connectivity is essential to evaluating non-

motorized plans and central to addressing part of the climate change dilemma.

Improved street and non-motorized connectivity increases accessibility and route options and reduces VMT and GHG. Traffic congestion, accidents and pollution emissions are reduced while mobility for non-drivers is increased. Emergency response improves because emergency vehicles have more direct access with less the risk that an area will become inaccessible if a particular part of the street network is blocked.

Systems Connectivity is ImportantRecent academic studies identified four land use and transportation factors

associated with walking and cycling, and the resulting reduction in VMT:

• Density: residential units within a specified area• Destinations: grocery stores, restaurant, retail, schools• Distance: to key destinations• Route: smaller blocks, better sidewalks

 

The optimization of routes in relations to these factors can help reduce VMT by as much as 35%, with similar reductions in vehicle energy consumption and emissions.

Achieving VMT Capita Reduction

-25

-20

-15

-10

-5

0%

Ch

an

ge i

n P

ers

on

Mil

es T

ravell

ed

Residential Office Park Retail / Service

Land Density Land Use Diversity Design

DESIGNAverage Block Size

% 4-Way Intersections% Sidewalk Coverage- 4 %

- 2 %

- 5%

Measures of connectivity helps indicate transportation-efficient land uses that yield lower VMT and GHG per capita

Research conducted in Seattle area by C. Lee and Anne Moudon (University of Washington), 2006: Quantifying Land Use and Urban Form Correlates of Walking

What is Route Directness Index?

straight-line distance “A”

BRDI = A / B

Aactual route distance “B”

Route Directness Index

Using ViaCityTM

Before After Impacted Parcels

IntersectionDensity

Link-Node Ratio

55.9 56.0

0.58 0.62 1,115

N/A

1.09 1.10 N/A

Example RDI - Existing Conditions

Shared-Use Path Connections

Using RDI to Test New Project / Plan

Shared-Use Path Connections

RDI is Sensitive to Critical Street Design

Shared-Use Path Connections

Sensitive to Block Length

Sensitive to Cul-de-Sac Length

305 ft 330ft

Integrating Green Infrastructure into Regional Planning

2010 APA Conference

New Orleans, LAApril 12, 2010